This proposal is a request for a 3 Tesla, whole-body, wide-bore magnetic resonance imaging system for the University of Colorado School of Medicine, Anschutz Medical Campus. The proposed instrument (3T Siemens MAGNETOM Skyra) would fulfill unmet research needs while providing greater scientific and funding opportunities for investigators across a wide range of departments and institutions. A major research interest at the UC School of Medicine is understanding and developing better treatments for schizophrenia and related mental illnesses. Because many of these studies involve auditory sensory processing, research is limited by the loud noise generated by our current scanner. The requested 3T Siemens scanner is markedly quieter than our current dated GE 3T MRI scanner, substantially improving our research capabilities in this area. In addition to benefiting our adult sensory processing and drug development studies, quieter scanning also would also greatly benefit a large newly- funded effort to understand the development of sensory processing and cognitive abilities in infants. Our current success rate for scanning infants is approximately 50%. The primary hindrance to scanning success is the noise of our current scanner, which often wakes the sleeping infants. In addition to being substantially quieter, parallel imaging and higher acceleration factors on the new scanner would allow for a shorter overall exam time, additionally increasing the likelihood of scan completion in this population. These factors would also result in less geometric distortion and signal dropout in the hippocampus and prefrontal cortex, brain areas thought to be critically important in the development of mental illness. Another major research focus that would benefit from the new system is our effort to understand the physiological and neurobiological basis of eating disorders, obesity and diabetes. A significant limitation for these studies is the narrow bore diameter of our current MR system. This limitation precludes scanning over 30% of obese subjects. This size limitation also is a key factor in spectroscopic studies of the liver, particulrly for those involving the measurement of 31P and 13C, which require a surface coil. In our present system, it is only feasible to study lean subjects, due to space required for the surface coil. A wide-bore system would enable multinuclear studies of the liver to access mitochondrial metabolism and liver glycogen, both important for diabetes and obesity studies. The proposed new system would also substantially improve important aspects of MRI-related research that would benefit all users, including 1) higher signal-to-noise ratios, 2) access to newer imaging techniques (e.g., arterial spin-labeling) not available on our current platform, 3) smaller magnet size, which can increase patient comfort and 4) elimination of our current limitation on the number of slices/volumes that can be acquired.